JPS62275982A - Elevator drive - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention provides an elevator drive device, specifically, a single induction motor that can be used both in normal times and in emergencies. This invention relates to an elevator drive device.

[Conventional technology]

As is well known, the rotation speed of an induction motor is given by the following formula (■).

20f N−−1・・・・・・・・・■ Here, the above N is the rotation speed (rpm) of the induction motor,
f is the frequency of the power supply (llz) and p is the number of poles of the induction motor. As is clear from this equation (2), in order to control the rotational speed of the induction motor, it is necessary to control the frequency f or change the number of poles p.

On the other hand, a conventional elevator drive device is configured as shown in FIG. 2, for example. That is, a terminal 1 for supplying commercial power is connected to a fixed terminal of a contact 2, and a movable terminal of this contact 2 is connected to an input end of an inverter 3 that converts the frequency of the commercial power to a high frequency. The output end of this inverter 3 is connected to a first induction motor 5 having a number of poles of 14, for example.
A second induction motor 6 is attached coaxially with the output shaft 5a of the induction motor [5.

This second induction motor 6 has, for example, 24 poles. A worm gear 12 is fixed to the tip of the output shaft 5a, and this worm gear 12 is
-It is engaged with machine 9. Further, a wire rope 10 is wound around this hoisting machine 9, an elevator car 8 is attached to one end of this wire rope 10, and a weight 11 is attached to the other end of this wire rope 10. Fixed.

Further, a relay circuit 4, which is a control circuit section, is connected to the inverter 3, and when an accident occurs, for example, when a signal is sent to this relay circuit 4, contacts 2 and 7 are switched. .

In the elevator system configured as described above, the high frequency output of the inverter 3 is normally supplied to the first induction motor 5, and the output shaft 5a is supplied with a high rotational speed.
rotates, and the car 8 moves up and down accordingly.

In addition, when it is necessary to move the elevator car 8 up and down slowly due to an accident, etc., a control signal indicating that there is an accident is sent from the inverter 3 to the relay circuit 4, and contacts 2 and 7 are connected to each other. By switching , commercial power is supplied to the second induction motor 6. In this way, as is clear from the above equation (2), the number of poles is large (
For example, 24), the rotational speed N becomes low, and the elevator can be operated at low speed.

[Problem to be solved]

By the way, the reason why the first induction motor for high speed and the second induction motor for low speed are provided as described above is as follows.

As mentioned above, the rotation speed of the induction motor can be changed by changing the frequency f as given by the above equation (2).

However, in conventional inverters, variable speed inverters that raise the frequency are very expensive, so in products such as elevators that have to lower prices as much as possible to compete with other companies. It was not easy to use.

Furthermore, since the conventional elevator drive apparatus uses the first and second induction motors as described above, the elevator drive apparatus as a whole is expensive.

[Means and effects for solving the problems] In order to solve the above problems, the present invention provides an inverter device that outputs a commercial power source by varying it to a predetermined frequency, and at least the output of the commercial power source or the inverter device. a control unit that selects either the commercial power source or the inverter device according to instructions from the control unit; a switch that is connected to the switch and connects the commercial power source or the inverter device; or a multi-pole induction motor to which any one of the outputs of the inverter device is supplied, so that the variable frequency output from the inverter device is supplied to the induction motor in normal times, and in an emergency, one - The output power of the commercial power source is supplied to the induction motor for low speed operation.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the elevator drive apparatus of this invention is demonstrated based on one Example of illustration.

FIG. 1 is a block diagram showing an elevator drive device of the present invention.

As shown in the figure, a terminal 21 for supplying commercial power is connected to an input terminal of an inverter device 22 and a first fixed terminal 29a of a switch 29, which will be described below.

The terminal 21 connected to the input end of the inverter device 22 is connected to the input end of a bridge 23 that converts alternating current to direct current, and is also connected to a control section 26. The output end 2 of the bridge 23 is connected to an electrolytic capacitor 24, and is further connected to a switching section 25 made of, for example, a transistor. and,
The output end of this switching section 25 is connected to the second fixed terminal 29I of the switch 29.

The control unit 26 is configured to be able to generate an accident signal in the event of an accident, for example, and this accident signal is supplied to a relay circuit 35. Further, the output signal of the relay circuit 35 is input to the control section 26, and the output signal from the error amplifier 28 is also supplied to the control section 26.

"-F; Fixed terminal 29C of isochi 29 is the induction motor 3
1, and the output shaft 3 of this induction motor 31]
A pulse encoder 32 for transmitting the rotational speed of the induction motor 31 as a pulse and a brake 33 are attached to the motor a. - A worm gear 41 is fixed to the tip of the output shaft 31a, and this worm gear 41 meshes with a hoist 42.

” - A wire rope 43 is wound around the hoisting a42, a basket 37 is suspended from one end of the wire rope 43, and a weight 34 is fixed to the other end of the wire rope 43. .

Then, when a person inside the car 37 presses a switch provided on the wall, the result is supplied to the input circuit 36. For example, the car 37 is moved to the floor specified by the instructions. It can be stopped.

Furthermore, a limit switch 38 is provided which is activated when the car 37 reaches a predetermined floor, and this limit switch 38 is connected to the input circuit 36.

The output end of the 1-input input circuit 36 is connected to the relay circuit 35 and the speed bump generator 27.

This speed pattern generator 27 is designed to generate a signal that gradually increases the speed by -1- when the motor starts moving from a stopped state, and is mainly designed to increase the speed by -1-. A pattern is beginning to emerge. The output end of the speed boost generator 27 is connected to an error amplifier 28. On the other hand, the pulse encoder 32 is connected to the error amplifier 28, and the speed pattern generator 27 and the pulse encoder 32
The control section 26
The signal is supplied to the

Further, from the output end of the relay circuit 35, a signal for selecting the output of the inverter device or the commercial power source is supplied to the contact point 29 (1).

Next, the operation of the elevator drive device configured as described above will be explained.

First, in normal times, the movable terminal 29c of the switch 29
and the second fixed terminal 29b are connected. In normal times, the inverter ff 22 supplies the induction motor 31 with a high frequency output of, for example, several 100 tlz. However, as is clear from the previous generation, the rotational speed of the induction motor 31 is maintained at a high level.

Therefore, the elevator car 37 moves at high speed, and since a signal is sent from the speed pattern generator 27 to the control unit 26 via the error amplifier circuit 28, when the elevator car 37 stops, The speed pattern when the speed is gradually increased from the beginning can be set to provide a comfortable ride.

When the car 37 reaches the floor number specified by the person riding in the car 37, an instruction signal is sent from the relay circuit 35 to the brake 33, which applies the brake and gradually reduces the speed. It will go and stop on that floor. Then, the limit switch 38 is activated to notify the input circuit 36 that the car 37 has reached the designated floor number.

Further, in the event that some kind of failure occurs in the elevator system, if the car 37 is to be slowly moved downward, an instruction is given to the control unit 26 using the hand J to indicate that an accident has occurred. Then, an accident signal is sent from the control unit 26 to the relay circuit 35, so the switch 29 is switched and the movable contact 29c and the first fixed contact 29a are connected. In such a state, commercial power is directly supplied to the −1-2 induction motor 31, so as is clear from the above equation (2), in this case the frequency f is, for example, 50 Hz, and the number of poles p is "24", then the rotation speed N &1
: r 250 J, which is a very low rotation speed. By moving the car 37 up and down slowly in this manner, necessary accident repair can be carried out.

〔effect〕

According to the present invention, high-speed operation in normal times and low-speed operation in emergencies can be performed with just one induction motor, so it is possible to construct an electric heater drive device at a very low cost.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an electric heater drive device showing an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional electric heater drive device. 1.21... Commercial power supply, 2.7.29.
...Contact, 3.22...Inverter device, 4.35
・・・・・・・・・Relay circuit, 5・・・・・・・・・
First induction motor, 6... Second induction motor, 8.37... Car, 23... Bridge, 25. ......Switching section, 26...
...Control unit, 27... Speed pattern generator, 31... Induction motor.

Claims (1)

[Scope of Claims] An inverter device that varies and outputs a commercial power source at a predetermined frequency; a control section that selects at least either the commercial power source or the output of the inverter device; A switch that selects and connects either the commercial power source or the inverter device according to instructions, and a multi-pole switch that is connected to the switch and is supplied with either the commercial power source or the output of the inverter device. and an induction motor, so that in normal times, variable frequency output from the inverter device is supplied to the induction motor, and in an emergency, the output of the commercial power source is supplied to the induction motor, thereby operating at a low speed. An elevator drive device characterized by: